this is not rocket science. take these assault rifles and weapons off the streets. >> piers is going to have a lot more on this story later tonight, 9:00 p.m. eastern. piers, thanks very much for joining us. >> thanks, wolf. thank you. >>> still ahead, incredible good fortune followed by a grisly death. authorities say a big lottery winner was poisoned. the mystery ahead. sorry. sore knee. blast of cold feels nice. why don't you use bengay zero degrees? it's the one you store in the freezer. same medicated pain reliever used by physical therapists. that's chilly. [ male announcer ] new bengay zero degrees. freeze and move on. >>> police now suspect that one man's good fortune may have been a motive for murder. >> it's an amazing story. they're investigating the death of a chicago man, who died of cyanide poisoning, just days after winning a huge lottery jackpot. >> cnn's mary snow is working the story for us. what are you finding out, mary? >> wolf, if it hadn't been for a tip from a family member to the medical